1. Field of the Invention
The present invention relates to a method and system for efficient storage and retrieval of a chain of spatial images, and more particularly, to a spatial image information method and system capable of efficiently retrieving spatial images by storing in a database the spatial images acquired through an image acquisition device, in which a global positioning system (GPS) and an inertial navigation system (INS) are combined, along with an interior orientation and exterior orientation, and maintaining meta information and indexes of the stored spatial images.
2. Background of the Related Art
Recently, as diverse services using a geographic information system (GIS) have widely been highlighted, there is an increasing interest in a spatial image information system for more efficient storage and retrieval of acquired spatial images. In order to construct the geographic information system is used a navigation system for acquiring spatial position information. The inertial navigation system (INS) and the global positioning system (GPS) are the widely used navigation systems.
The INS is a system for finding navigation information of an object using an accelerometer and a gyro, and is used in a flying object or a ship. This INS is not affected by an external environment, and has the advantage in that it provides very accurate and sequential navigation data for a short period of voyage, while it has the disadvantage in that errors are accumulated for a long period of voyage.
Meanwhile, the global positioning system (GPS) is a system for acquiring the position, speed, etc., of an object by measuring the distance between the object and at least four satellites among 24 orbiting satellites going round the earth. This GPS has the advantage in that errors are not accumulated with the lapse of time and it is inexpensive, but has the disadvantage in that its performance deteriorates if at least four orbiting satellites are not secured. Accordingly, researches for combining the two systems are actively in progress since the two systems are complementary.
The term ‘spatial image’ means an aerial image or a satellite image acquired by an airplane or a satellite that mounts the GPS or INS, or an image acquired by an image acquisition device such as a CCD camera of a moving vehicle such as a GPS van that mounts a GPS/INS combined system. Such a spatial image has the advantage in that it is possible to measure spatial information within the image by way of an exterior orientation composed of a camera position (x,y,z), accelerated velocity, slope and direction at the moment the image is acquired, and an interior orientation acquired by a camera calibration. Since this spatial image is of a large capacity, a spatial image information system for the efficient storage and management thereof is required.
However, the conventional spatial image information systems have the problems in that they use a method of simply storing related data in a file system in the unit of a file or a directory, or simply use only an interface of a database system as they cannot support an effective retrieving method for the spatial images even though they use the database, thereby deteriorating the their performance.